Old District
The area referred to as the Old District was frequently called by other names, such as "the depths of Coruscant" or "the underworld." This area served as a refuge for individuals without homes and those fleeing from the law on Coruscant. Moreover, during the time of the Yuuzhan Vong War, it provided sanctuary to the Shamed Ones belonging to the Yuuzhan Vong.
History
It is generally accepted that the Old District represents the earliest construction on Coruscant, although certain historians suggest that development might have occurred at even lower levels.